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1.
Transplant Cell Ther ; 30(8): 776-787, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38762057

RESUMO

Genetically modified cell therapies (GMCT), particularly immune effector cells (IEC) such as chimeric receptor antigen (CAR) T cells, have shown promise in curing cancer and rare diseases after a single treatment course. Following close behind CAR T approvals are GMCT based on hematopoietic stem cells, such as products developed for hemoglobinopathies and other disorders. Academically sponsored GMCT products, often developed in academic centers without industry involvement, face challenges in sustaining access after completion of early phase studies when there is no commercial partner invested in completing registration trials for marketing applications. The American Society for Transplantation and Cellular Therapy (ASTCT) formed a task force named ACT To Sustain (Adoptive Cell Therapy to Sustain) to address the "valley of death" of academic GMCT products. This paper presents the task force's findings and considerations regarding financial sustainability of academically sponsored GMCT products in the absence of commercial development. We outline case scenarios illustrating barriers to maintaining access to promising GMCT developed by academic centers. The paper also delves into the current state of GMCT development, commercialization, and reimbursement, citing examples of abandoned products, cost estimates associated with GMCT manufacturing and real-world use of cost recovery. We propose potential solutions to address the financial, regulatory, and logistical challenges associated with sustaining access to academically sponsored GMCT products and to ensure that products with promising results do not languish in a "valley of death" due to financial or implementational barriers. The suggestions include aligning US Food and Drug Administration (FDA) designations with benefit coverage, allowing for cost recovery of certain products as a covered benefit, and engaging with regulators and policy makers to discuss alternative pathways for academic centers to provide access. We stress the importance of sustainable access to GMCT and call for collaborative efforts to develop regulatory pathways that support access to academically sponsored GMCT products.


Assuntos
Imunoterapia Adotiva , Humanos , Imunoterapia Adotiva/economia , Imunoterapia Adotiva/legislação & jurisprudência , Imunoterapia Adotiva/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Terapia Baseada em Transplante de Células e Tecidos/ética , Estados Unidos , Acessibilidade aos Serviços de Saúde , Receptores de Antígenos Quiméricos , United States Food and Drug Administration
2.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37171234

RESUMO

The Oak Ridge National Laboratory is planning to build the Second Target Station (STS) at the Spallation Neutron Source (SNS). STS will host a suite of novel instruments that complement the First Target Station's beamline capabilities by offering an increased flux for cold neutrons and a broader wavelength bandwidth. A novel neutron imaging beamline, named the Complex, Unique, and Powerful Imaging Instrument for Dynamics (CUPI2D), is among the first eight instruments that will be commissioned at STS as part of the construction project. CUPI2D is designed for a broad range of neutron imaging scientific applications, such as energy storage and conversion (batteries and fuel cells), materials science and engineering (additive manufacturing, superalloys, and archaeometry), nuclear materials (novel cladding materials, nuclear fuel, and moderators), cementitious materials, biology/medical/dental applications (regenerative medicine and cancer), and life sciences (plant-soil interactions and nutrient dynamics). The innovation of this instrument lies in the utilization of a high flux of wavelength-separated cold neutrons to perform real time in situ neutron grating interferometry and Bragg edge imaging-with a wavelength resolution of δλ/λ ≈ 0.3%-simultaneously when required, across a broad range of length and time scales. This manuscript briefly describes the science enabled at CUPI2D based on its unique capabilities. The preliminary beamline performance, a design concept, and future development requirements are also presented.

3.
ChemSusChem ; 16(3): e202201864, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36336661

RESUMO

Understanding the mechanism of iron-catalyzed graphitization of biomass is an important step for the large-scale synthesis of green graphene. Although iron is known to be the most active transition metal for the catalytic graphitization of cellulose-derived biochar, the direct effect of the iron molecular structure on the formation of highly graphitic carbon remains elusive. Here, biochar was produced from pyrolysis of iron-impregnated cellulose at three different temperatures (1000, 1400, and 1800 °C). X-ray diffraction, X-ray photoelectron spectroscopy, and magnetic measurements were used to probe changes in biochar nanostructure catalyzed by the inclusion of iron. An increase of pyrolysis temperature led to an increase in the iron particle size and the degree of iron reduction, as well as the formation of larger graphitic carbon crystallite sizes, and these two attributes of iron were seen to positively affect the biochar graphitization usually challenging under 2000 °C.

4.
Blood ; 141(6): 609-619, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351239

RESUMO

Children living in poverty experience excessive relapse and death from newly diagnosed acute lymphoblastic leukemia (ALL). The influence of household poverty and neighborhood social determinants on outcomes from chimeric antigen receptor (CAR) T-cell therapy for relapsed/refractory (r/r) leukemia is poorly described. We identified patients with r/r CD19+ ALL/lymphoblastic lymphoma treated on CD19-directed CAR T-cell clinical trials or with commercial tisagenlecleucel from 2012 to 2020. Socioeconomic status (SES) was proxied at the household level, with poverty exposure defined as Medicaid-only insurance. Low-neighborhood opportunity was defined by the Childhood Opportunity Index. Among 206 patients aged 1 to 29, 35.9% were exposed to household poverty, and 24.9% had low-neighborhood opportunity. Patients unexposed to household poverty or low-opportunity neighborhoods were more likely to receive CAR T-cell therapy with a high disease burden (>25%), a disease characteristic associated with inferior outcomes, as compared with less advantaged patients (38% vs 30%; 37% vs 26%). Complete remission (CR) rate was 93%, with no significant differences by household poverty (P = .334) or neighborhood opportunity (P = .504). In multivariate analysis, patients from low-opportunity neighborhoods experienced an increased hazard of relapse as compared with others (P = .006; adjusted hazard ratio [HR], 2.3; 95% confidence interval [CI], 1.3-4.1). There was no difference in hazard of death (P = .545; adjusted HR, 1.2; 95% CI, 0.6-2.4). Among children who successfully receive CAR T-cell therapy, CR and overall survival are equitable regardless of proxied SES and neighborhood opportunity. Children from more advantaged households and neighborhoods receive CAR T-cell therapy with a higher disease burden. Investigation of multicenter outcomes and access disparities outside of clinical trial settings is warranted.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptores de Antígenos Quiméricos , Humanos , Criança , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Recidiva , Antígenos CD19 , Pobreza
5.
Kidney Int Rep ; 7(8): 1793-1801, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35967105

RESUMO

Introduction: Treatment of anemia in dialysis patients has been associated with increased risk of vascular access thrombosis (VAT). Proactive IV irOn Therapy in hemodiALysis Patients (PIVOTAL) was a clinical trial of proactive compared with reactive i.v. iron therapy in patients requiring hemodialysis. We analyzed the trial data to determine whether randomized treatment arm, alongside other clinical and laboratory variables, independently associated with VAT. Methods: In PIVOTAL, 2141 adult patients were randomized. The type of vascular access (arteriovenous fistula [AVF], arteriovenous graft [AVG], or central venous catheter [CVC]) was recorded at baseline and every month after randomization. The associations between clinical and laboratory data and first VAT were evaluated in a multivariate analysis. Results: A total of 480 (22.4%) participants experienced VAT in a median of 2.1 years of follow-up. In multivariable analyses, treatment arm (proactive vs. reactive) was not an independent predictor of VAT (hazard ratio [HR] 1.13, P = 0.18). Diabetic kidney disease (HR 1.45, P < 0.001), AVG use (HR 2.29, P < 0.001), digoxin use (HR 2.48, P < 0.001), diuretic use (HR 1.25, P = 0.02), female sex (HR 1.33, P = 0.002), and previous/current smoker (HR 1.47, P = 0.004) were independently associated with a higher risk of VAT. Angiotensin receptor blocker (ARB) use (HR 0.66, P = 0.01) was independently associated with a lower risk of VAT. Conclusion: In PIVOTAL, VAT occurred in nearly 1 quarter of participants in a median of just >2 years. In this post hoc analysis, randomization to proactive i.v. iron treatment arms did not increase the risk of VAT.

6.
Kidney360 ; 2(11): 1761-1769, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-35372992

RESUMO

Background: People with kidney failure treated with hemodialysis (HD) are at increased risk of stroke compared with similarly aged people with normal kidney function. One concern is that treatment of renal anemia might increase stroke risk. We studied risk factors for stroke in a prespecified secondary analysis of a randomized, controlled trial of intravenous iron treatment strategies in HD. Methods: We analyzed data from the Proactive IV Iron Therapy in Haemodialysis Patients (PIVOTAL) trial, focusing on variables associated with risk of stroke. The trial randomized 2141 adults who had started HD <12 months earlier and who were receiving an erythropoiesis-stimulating agent (ESA) to high-dose IV iron administered proactively or low-dose IV iron administered reactively in a 1:1 ratio. Possible stroke events were independently adjudicated. We performed analyses to identify variables associated with stroke during follow-up and assessed survival following stroke. Results: During a median 2.1 years of follow-up, 69 (3.2%) patients experienced a first postrandomization stroke. Fifty-seven (82.6%) were ischemic strokes, and 12 (17.4%) were hemorrhagic strokes. There were 34 postrandomization strokes in the proactive arm and 35 postrandomization strokes in the reactive arm (hazard ratio, 0.90; 95% confidence interval, 0.56 to 1.44; P=0.66). In multivariable models, women, diabetes, history of prior stroke at baseline, higher baseline systolic BP, lower serum albumin, and higher C-reactive protein were independently associated with stroke events during follow-up. Hemoglobin, total iron, and ESA dose were not associated with risk of stroke. Fifty-eight percent of patients with a stroke event died during follow-up compared with 23% without a stroke. Conclusions: In patients on HD, stroke risk is broadly associated with risk factors previously described to increase cardiovascular risk in this population. Proactive intravenous iron does not increase stroke risk.Clinical Trial registry name and registration number: Proactive IV Iron Therapy in Haemodialysis Patients (PIVOTAL), 2013-002267-25.


Assuntos
Anemia , Hematínicos , Acidente Vascular Cerebral , Adulto , Idoso , Anemia/induzido quimicamente , Feminino , Hematínicos/efeitos adversos , Humanos , Ferro/efeitos adversos , Diálise Renal/efeitos adversos , Acidente Vascular Cerebral/epidemiologia
7.
J Am Soc Nephrol ; 31(5): 1118-1127, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32253271

RESUMO

BACKGROUND: Experimental and observational studies have raised concerns that giving intravenous (IV) iron to patients, such as individuals receiving maintenance hemodialysis, might increase the risk of infections. The Proactive IV Iron Therapy in Haemodialysis Patients (PIVOTAL) trial randomized 2141 patients undergoing maintenance hemodialysis for ESKD to a high-dose or a low-dose IV iron regimen, with a primary composite outcome of all-cause death, heart attack, stroke, or hospitalization for heart failure. Comparison of infection rates between the two groups was a prespecified secondary analysis. METHODS: Secondary end points included any infection, hospitalization for infection, and death from infection; we calculated cumulative event rates for these end points. We also interrogated the interaction between iron dose and vascular access (fistula versus catheter). RESULTS: We found no significant difference between the high-dose IV iron group compared with the lose-dose group in event rates for all infections (46.5% versus 45.5%, respectively, which represented incidences of 63.3 versus 69.4 per 100 patient years, respectively); rates of hospitalization for infection (29.6% versus 29.3%, respectively) also did not differ. We did find a significant association between risk of a first cardiovascular event and any infection in the previous 30 days. Compared with patients undergoing dialysis with an arteriovenous fistula, those doing so via a catheter had a higher incidence of having any infection, hospitalization for infection, or fatal infection, but IV iron dosing had no effect on these outcomes. CONCLUSIONS: The high-dose and low-dose IV iron groups exhibited identical infection rates. Risk of a first cardiovascular event strongly associated with a recent infection.


Assuntos
Infecções/etiologia , Ferro/administração & dosagem , Diálise Renal/efeitos adversos , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/etiologia , Causas de Morte , Infecção Hospitalar/epidemiologia , Relação Dose-Resposta a Droga , Feminino , Hospitalização , Humanos , Infecções/epidemiologia , Infusões Intravenosas , Ferro/uso terapêutico , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Diálise Renal/instrumentação , Análise de Sobrevida
8.
N Engl J Med ; 380(5): 447-458, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30365356

RESUMO

BACKGROUND: Intravenous iron is a standard treatment for patients undergoing hemodialysis, but comparative data regarding clinically effective regimens are limited. METHODS: In a multicenter, open-label trial with blinded end-point evaluation, we randomly assigned adults undergoing maintenance hemodialysis to receive either high-dose iron sucrose, administered intravenously in a proactive fashion (400 mg monthly, unless the ferritin concentration was >700 µg per liter or the transferrin saturation was ≥40%), or low-dose iron sucrose, administered intravenously in a reactive fashion (0 to 400 mg monthly, with a ferritin concentration of <200 µg per liter or a transferrin saturation of <20% being a trigger for iron administration). The primary end point was the composite of nonfatal myocardial infarction, nonfatal stroke, hospitalization for heart failure, or death, assessed in a time-to-first-event analysis. These end points were also analyzed as recurrent events. Other secondary end points included death, infection rate, and dose of an erythropoiesis-stimulating agent. Noninferiority of the high-dose group to the low-dose group would be established if the upper boundary of the 95% confidence interval for the hazard ratio for the primary end point did not cross 1.25. RESULTS: A total of 2141 patients underwent randomization (1093 patients to the high-dose group and 1048 to the low-dose group). The median follow-up was 2.1 years. Patients in the high-dose group received a median monthly iron dose of 264 mg (interquartile range [25th to 75th percentile], 200 to 336), as compared with 145 mg (interquartile range, 100 to 190) in the low-dose group. The median monthly dose of an erythropoiesis-stimulating agent was 29,757 IU in the high-dose group and 38,805 IU in the low-dose group (median difference, -7539 IU; 95% confidence interval [CI], -9485 to -5582). A total of 320 patients (29.3%) in the high-dose group had a primary end-point event, as compared with 338 (32.3%) in the low-dose group (hazard ratio, 0.85; 95% CI, 0.73 to 1.00; P<0.001 for noninferiority; P=0.04 for superiority). In an analysis that used a recurrent-events approach, there were 429 events in the high-dose group and 507 in the low-dose group (rate ratio, 0.77; 95% CI, 0.66 to 0.92). The infection rate was the same in the two groups. CONCLUSIONS: Among patients undergoing hemodialysis, a high-dose intravenous iron regimen administered proactively was superior to a low-dose regimen administered reactively and resulted in lower doses of erythropoiesis-stimulating agent being administered. (Funded by Kidney Research UK; PIVOTAL EudraCT number, 2013-002267-25 .).


Assuntos
Anemia/tratamento farmacológico , Óxido de Ferro Sacarado/administração & dosagem , Hematínicos/administração & dosagem , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Administração Intravenosa , Adulto , Idoso , Anemia/etiologia , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Óxido de Ferro Sacarado/efeitos adversos , Ferritinas/sangue , Seguimentos , Hematínicos/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego , Transferrina/análise
9.
Am J Nephrol ; 48(4): 260-268, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30304714

RESUMO

BACKGROUND: Intravenous (IV) iron supplementation is a standard maintenance treatment for hemodialysis (HD) patients, but the optimum dosing regimen is unknown. METHODS: PIVOTAL (Proactive IV irOn Therapy in hemodiALysis patients) is a multicenter, open-label, blinded endpoint, randomized controlled (PROBE) trial. Incident HD adults with a serum ferritin < 400 µg/L and transferrin saturation (TSAT) levels < 30% receiving erythropoiesis-stimulating agents (ESA) were eligible. Enrolled patients were randomized to a proactive, high-dose IV iron arm (iron sucrose 400 mg/month unless ferritin > 700 µg/L and/or TSAT ≥40%) or a reactive, low-dose IV iron arm (iron sucrose administered if ferritin <200 µg/L or TSAT < 20%). We hypothesized that proactive, high-dose IV iron would be noninferior to reactive, low-dose IV iron for the primary outcome of first occurrence of nonfatal myocardial infarction (MI), nonfatal stroke, hospitalization for heart failure or death from any cause. If noninferiority is confirmed with a noninferiority limit of 1.25 for the hazard ratio of the proactive strategy relative to the reactive strategy, a test for superiority will be carried out. Secondary outcomes include infection-related endpoints, ESA dose requirements, and quality-of-life measures. As an event-driven trial, the study will continue until at least 631 primary outcome events have accrued, but the expected duration of follow-up is 2-4 years. RESULTS: Of the 2,589 patients screened across 50 UK sites, 2,141 (83%) were randomized. At baseline, 65.3% were male, the median age was 65 years, and 79% were white. According to eligibility criteria, all patients were on ESA at screening. Prior stroke and MI were present in 8 and 9% of the cohort, respectively, and 44% of patients had diabetes at baseline. Baseline data for the randomized cohort were generally concordant with recent data from the UK Renal Registry. CONCLUSIONS: PIVOTAL will provide important information about the optimum dosing of IV iron in HD patients representative of usual clinical practice. TRIAL REGISTRATION: EudraCT number: 2013-002267-25.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Óxido de Ferro Sacarado/administração & dosagem , Hematínicos/administração & dosagem , Falência Renal Crônica/complicações , Diálise Renal/efeitos adversos , Administração Intravenosa , Idoso , Anemia Ferropriva/sangue , Anemia Ferropriva/etiologia , Relação Dose-Resposta a Droga , Feminino , Óxido de Ferro Sacarado/efeitos adversos , Ferritinas/sangue , Seguimentos , Hematínicos/efeitos adversos , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Trombose/induzido quimicamente , Trombose/epidemiologia , Resultado do Tratamento
10.
Rheumatol Int ; 38(9): 1623-1634, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29556750

RESUMO

The aim of this systematic review was to evaluate the evidence from randomised controlled trials (RCTs) evaluating the effectiveness of interactive digital interventions (IDIs) for physical activity (PA) and health related quality of life (HRQoL) in people with Inflammatory Arthritis [rheumatoid arthritis (RA), juvenile idiopathic arthritis (JIA) axial Spondyloarthritis (AS) and psoriatic arthritis (PsA)]. Seven electronic databases identified published and unpublished studies. Two reviewers conducted independent data extraction and quality assessment using the Cochrane risk of bias tool (RoB). The primary outcome was change in objective PA after the intervention; secondary outcomes included self-reported PA and HRQoL after the intervention and objective or self-reported PA at least 1 year later. Five manuscripts, reporting four RCTs (three high and one low RoB) representing 492 (459 RA, 33 JIA) participants were included. No trials studying PsA or AS met the inclusion criteria. Interventions ranged from 6 to 52 weeks and included 3-18 Behaviour Change Techniques. Due to heterogeneity of outcomes, a narrative synthesis was conducted. No trials reported any significant between group differences in objective PA at end of intervention. Only one low RoB trial found a significant between group difference in self-reported vigorous [MD Δ 0.9 days (95% CI 0.3, 1.5); p = 0.004], but not moderate, PA in people with RA but not JIA. There were no between group differences in any other secondary outcomes. There is very limited evidence for the effectiveness of IDIs on PA and HRQoL in RA and JIA and no evidence for their effectiveness in PsA or AS.


Assuntos
Artrite Reumatoide/complicações , Exercício Físico/fisiologia , Qualidade de Vida , Espondilartrite/complicações , Artrite Reumatoide/psicologia , Seguimentos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Espondilartrite/psicologia
11.
ChemMedChem ; 13(4): 312-320, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29331080

RESUMO

The NLRP3 inflammasome is an important regulator of the sterile inflammatory response, and its activation by host-derived sterile molecules leads to the intracellular activation of caspase-1, processing of the pro-inflammatory cytokines interleukin-1ß (IL-1ß)/IL-18, and pyroptotic cell death. Inappropriate activation of NLRP3 drives a chronic inflammatory response and is implicated in several non-communicable diseases, including gout, atherosclerosis, type II diabetes and Alzheimer's disease. In this study, we report the design, synthesis and biological evaluation of novel boron compounds (NBCs) as NLRP3 inflammasome inhibitors. Structure-activity relationships (SAR) show that 4-fluoro substituents on the phenyl rings retain NLRP3 inhibitory activity, whereas more steric and lipophilic substituents diminish activity. Loss of inhibitory activity is also observed if the CCl3 group on the oxazaborine ring is replaced by a CF3 group. These findings provide additional understanding of the NBC series and will aid in the development of these NLRP3 inhibitors as tool compounds or therapeutic candidates for sterile inflammatory diseases.


Assuntos
Anti-Inflamatórios/síntese química , Compostos de Boro/química , Desenho de Fármacos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Células da Medula Óssea/citologia , Compostos de Boro/síntese química , Compostos de Boro/farmacologia , Células Cultivadas , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Relação Estrutura-Atividade
12.
Cell Chem Biol ; 24(11): 1321-1335.e5, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28943355

RESUMO

NLRP3 is a receptor important for host responses to infection, yet is also known to contribute to devastating diseases such as Alzheimer's disease, diabetes, atherosclerosis, and others, making inhibitors for NLRP3 sought after. One of the inhibitors currently in use is 2-aminoethoxy diphenylborinate (2APB). Unfortunately, in addition to inhibiting NLRP3, 2APB also displays non-selective effects on cellular Ca2+ homeostasis. Here, we use 2APB as a chemical scaffold to build a series of inhibitors, the NBC series, which inhibit the NLRP3 inflammasome in vitro and in vivo without affecting Ca2+ homeostasis. The core chemical insight of this work is that the oxazaborine ring is a critical feature of the NBC series, and the main biological insight the use of NBC inhibitors led to was that NLRP3 inflammasome activation was independent of Ca2+. The NBC compounds represent useful tools to dissect NLRP3 function, and may lead to oxazaborine ring-containing therapeutics.


Assuntos
Boro/química , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Animais , Células da Medula Óssea/citologia , Boro/farmacologia , Compostos de Boro/química , Compostos de Boro/metabolismo , Compostos de Boro/farmacologia , Cálcio/metabolismo , Células Cultivadas , Cristalografia por Raios X , Humanos , Concentração Inibidora 50 , Interleucina-1beta/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Conformação Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Relação Estrutura-Atividade
13.
Nat Commun ; 7: 12504, 2016 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-27509875

RESUMO

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit cyclooxygenase-1 (COX-1) and COX-2 enzymes. The NLRP3 inflammasome is a multi-protein complex responsible for the processing of the proinflammatory cytokine interleukin-1ß and is implicated in many inflammatory diseases. Here we show that several clinically approved and widely used NSAIDs of the fenamate class are effective and selective inhibitors of the NLRP3 inflammasome via inhibition of the volume-regulated anion channel in macrophages, independently of COX enzymes. Flufenamic acid and mefenamic acid are efficacious in NLRP3-dependent rodent models of inflammation in air pouch and peritoneum. We also show therapeutic effects of fenamates using a model of amyloid beta induced memory loss and a transgenic mouse model of Alzheimer's disease. These data suggest that fenamate NSAIDs could be repurposed as NLRP3 inflammasome inhibitors and Alzheimer's disease therapeutics.


Assuntos
Doença de Alzheimer/prevenção & controle , Anti-Inflamatórios não Esteroides/farmacologia , Ácido Flufenâmico/farmacologia , Inflamassomos/metabolismo , Ácido Mefenâmico/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doença de Alzheimer/metabolismo , Animais , Células da Medula Óssea/metabolismo , Morte Celular , Canais de Cloreto/metabolismo , Cisteína/metabolismo , Feminino , Genótipo , Inflamação , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Transtornos da Memória/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Reconhecimento Visual de Modelos/efeitos dos fármacos , Ratos
14.
J Virol ; 90(1): 356-67, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26468525

RESUMO

UNLABELLED: The ability of Epstein-Barr virus (EBV) to spread and persist in human populations relies on a balance between host immune responses and EBV immune evasion. CD8(+) cells specific for EBV late lytic cycle antigens show poor recognition of target cells compared to immediate early and early antigen-specific CD8(+) cells. This phenomenon is due in part to the early EBV protein BILF1, whose immunosuppressive activity increases with lytic cycle progression. However, published data suggest the existence of a hitherto unidentified immune evasion protein further enhancing protection against late EBV antigen-specific CD8(+) cells. We have now identified the late lytic BDLF3 gene as the missing link accounting for efficient evasion during the late lytic cycle. Interestingly, BDLF3 also contributes to evasion of CD4(+) cell responses to EBV. We report that BDLF3 downregulates expression of surface major histocompatibility complex (MHC) class I and class II molecules in the absence of any effect upon other surface molecules screened, including CD54 (ICAM-1) and CD71 (transferrin receptor). BDLF3 both enhanced internalization of surface MHC molecules and reduced the rate of their appearance at the cell surface. The reduced expression of surface MHC molecules correlated with functional protection against CD8(+) and CD4(+) T cell recognition. The molecular mechanism was identified as BDLF3-induced ubiquitination of MHC molecules and their subsequent downregulation in a proteasome-dependent manner. IMPORTANCE: Immune evasion is a necessary feature of viruses that establish lifelong persistent infections in the face of strong immune responses. EBV is an important human pathogen whose immune evasion mechanisms are only partly understood. Of the EBV immune evasion mechanisms identified to date, none could explain why CD8(+) T cell responses to late lytic cycle genes are so infrequent and, when present, recognize lytically infected target cells so poorly relative to CD8(+) T cells specific for early lytic cycle antigens. The present work identifies an additional immune evasion protein, BDLF3, that is expressed late in the lytic cycle and impairs CD8(+) T cell recognition by targeting cell surface MHC class I molecules for ubiquitination and proteasome-dependent downregulation. Interestingly, BDLF3 also targets MHC class II molecules to impair CD4(+) T cell recognition. BDLF3 is therefore a rare example of a viral protein that impairs both the MHC class I and class II antigen-presenting pathways.


Assuntos
Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/fisiologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Evasão da Resposta Imune , Glicoproteínas de Membrana/metabolismo , Ubiquitinação , Proteínas Virais/metabolismo , Linhagem Celular , Regulação para Baixo , Humanos , Complexo Principal de Histocompatibilidade , Proteínas de Membrana/metabolismo , Linfócitos T/imunologia
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